The chemical oxygen-iodine laser (COIL) is a short wavelength high-power chemical laser with wide ranging industrial, technological, and military applications. The COIL produces a laser beam with a 1.315-μm wavelength, which is well suited to a variety of uses. The COIL also has one of the best beam qualities of any available laser, which allows for clean cuts and welds, as well as simple beam correction and direction.
COILs are powered by solutions of basic hydrogen peroxide (BHP). BHP is generated by the combination of alkali hydroxide, including lithium, sodium, and potassium hydroxide, with hydrogen peroxide according to the equation:OH−+H2O2+M+→O2H−+H2O+M+  (I)where M+ is any of the Li+, Na+ or K+ ions, or other suitable ions, or mixture of these ions. The term BHP typically refers to a solution having 4 molar to 8 molar concentration of perhydroxyl ion (O2H−), which is formed by the reaction:OH−+H2O2→O2H−+H2O  (II)
The perhydroxyl anions and alkali cations of the aqueous BHP solution are then reacted with chlorine gas according to the equation:Cl2+2O2H−+2M+→H2O2+2MCl+O2(1Δ)  (III)The resultant singlet delta oxygen (O2(1Δ)) is an excited state of oxygen. Water vapor may be removed from the products of reaction (III) and the products are accelerated to supersonic velocity in an expansion nozzle to create a laser gain region. Molecular iodine is injected and mixed with the gas flow. The singlet delta oxygen has a resonance frequency very close to the resonance frequency of atomic iodine and, when intermingled, the singlet delta oxygen causes the rapid dissociation of the diatomic iodine molecule and the excitation of the iodine atoms. Energy is released in the form of light, which is extracted from the excited iodine atoms by a laser resonator positioned transverse to the direction of gas flow. The exhaust gases are usually removed and scrubbed to remove residual chlorine and iodine. The BHP is recycled until approximately 50-mol % of the perhydroxyl anions have been used.
In order to generate the high-power laser required for industrial and military applications, a COIL requires large initial volumes of alkali hydroxides and hydrogen peroxide. The need to transport and store large volumes of these materials presents a large hazard, especially in the industrial and military environments in which they will be used. Concentrated alkali hydroxides are extremely corrosive. Concentrated hydrogen peroxide is also a logistical problem. H2O2 is extremely reactive and subject to autocatalytic decomposition as well as rapid decomposition upon exposure to a variety of trace impurities. The decomposition may be accelerated by exposure to agitation, exposure to rough surfaces, or exposure to metals.
Several prior art references teach methods of recycling BHP after use so that fresh supplies of H2O2 need not be supplied during operation of a COIL, but there still remains the problems presented by transportation and storage of the large initial volumes of H2O2 and MOH required for operation of the COIL device.
What is needed is a method of supplying large quantities of BHP, on-site, to a COIL device without the hazardous transportation and long-term storage of peroxide and caustic alkali hydroxide materials.